For remote control of a speed change gear used in a vehicle, there is known a shift and select system, a torsion shaft system, and a cam system.
In a shift mechanism of the shift and select system, a shift fork shaft connected with a shift fork is provided on end portions thereof with a shift shaft for performing only shifting and a select shaft for performing only selecting. These two shafts are arranged in perpendicular relation with each other, and the shift lever and select lever are connected to the outer sides of the speed change gear so that speed change is realized by the respective levers.
As for the shift mechanism, one thereof is disclosed in Japanese Utility Model Publication No. Sho 56-35854. A transmission control apparatus for an automotive vehicle as disclosed in this publication is designed such that a control rod of a control lever is communicated with a select outer lever and shift idle lever each through a rod, and it can be easily changed from a remote control system to a floor shift method, thereby simplifying the manufacture of the transmission control apparatus and simplifying the factory facilities and production management.
In Japanese Utility Model Publication No. Sho 62-27926 there is disclosed a supporting structure of an outer cable of a remote control system speed change gear operating mechanism using a push cable, which supporting structure supports the end portion on the speed change gear side of the outer cable through a comparatively soft elastic body capable of absorbing vibrations. The end portion on the side of the speed change gear operating lever of the outer cable is either rigidly supported or supported through a comparatively hard elastic body. Vibration of a power plant system is mostly absorbed by the comparatively soft elastic body, thereby to reduce the generation of noises in the vehicle interior.
Furthermore, considering Japanese Utility Model Publication No. Sho 64-7386, a shift mechanism disclosed in this publication is designed such that a control lever includes a lever body and a select arm member has a ball portion on a tip thereof, and a retainer is rotatably provided with a shaft integrally having a first lever connected to a select operating lever and extending in the horizontal direction, the shaft being integrally connected thereon with a second lever which is to be brought into a connection with the ball portion formed on the tip of the select arm member, thereby forming two kinds of shift mechanisms which can be applied to a transmission having different select directions.
A conventional remote control system shift mechanism 110, as shown in FIGS. 9 through 11, includes a shift and select shaft 112 inserted at right angles with respect to a transmission case 108 of a manual speed change gear 106 for use in a vehicle. One end of this shift and select shaft 112 is slidingly movably provided with a link mounting portion 150 having on its upper portion a shift lever 114 and a select lever 120. The reference numeral 146 is a clutch cable.
The shift lever 114 is connected with one end of a shift cable 142 and the select lever 120 is connected with one end of a select cable 144. The other ends of the respective cables 142 and 144 are connected with a speed change operating lever (not shown), thereby to perform the shift and/or select operation of the manual speed change gear 106 by this speed change operating lever.
However, in the above-mentioned shift mechanism, as shown in FIG. 9, the angles .alpha. and .beta. of the shift and select cables 142 and 144 with respect to vertical planes oriented transversely of the vehicle are small. Thus, when the other ends of the respective cables 142 and 144 are wired at the front side of the vehicle, the curved states of the respective cables 142 and 144 become large. That is, the cables 142 and 144 must bend substantially. As a consequence, there is significant resistance generated due to the large curve or bending of the respective cables 142 and 144 at the shift or select operations, and the speed change operating feeling is jeopardized.
Also, because the curved states (bends) of the shift and select cables become large, positioning the respective cables becomes difficult and thus practically disadvantageous.
In order to eliminate the above-mentioned inconveniences, the present invention provides a shift mechanism capable of making the bends of a shift cable for connection to a shift lever and a select cable for connection to a select lever small. This permits generally linearly wiring of the respective cables in order to reduce resistance at the shift or select operation and improve the speed change operating feeling, and permits positioning of the respective cables with ease.
The present invention is preferably constructed such that in a shift mechanism for a speed change gear mounted in a horizontal posture on a horizontal engine which is mounted on a rear side of a four wheel drive vehicle, said shift mechanism includes a shift cable and a select cable which are generally linearly wired from the front to the rear of the vehicle. The shift mechanism also includes a first engaging portion and a first link mechanism for converting rotational motion of a shift lever, as transmitted to the shift lever through said shift cable, to a reciprocating motion of a shift and select shaft. The shift mechanism further includes a second engaging portion and second link mechanism for converting rotational motion of a select lever, as transmitted to the select lever through said select cable, to a reciprocating motion of said shift and select shaft.
Due to the present invention, constructed as mentioned above, when the shift cable of the shift mechanism is connected to the shift lever and the select cable is connected to the select lever, that is, when the wiring work or cabling is performed, the curves or bends of the shift cable and the select cable are made small in order to define generally linear cabling and reduce the resistance during the shift or select operation, thereby improving the speed change operating feeling and making the operation of the respective cables easy.